Cams.......anyone

[TiPerformance]

Hi I have a 98 318ti 5 spd. I am very pleased with the car, however the mod sickness had caught me again.

I have the money to go out and get cams from Bekkers or BMPD, but to me that seems too simple. What I am looking to do is see if there are any other cams from the older s14 or m42 engine that will make more power for my M44 engine. I am currently having trouble finding specs on any of the BMW cams, so if anyone can help, I would greatly appriciate it. My last resort is to order the cams from the dealer have them measured then return them.

Now for those of you that think there is no chance that cams will be interchangeable need to look at GM 2.3L and 2.4L DOHC engines. Like the BMW engine the GM engine went up .1L in 1996 when auto manafactures switched to OBD2 emissions systems. In the 2.4L engine the 2.3L intake cam swapped to the 2.4L makes a decent increase in power. I am not saying that the BMW engines will be the same, but I feel it is worth a shot.

I am also trying to research other things that might increase performance on the M44 from the other engines, such as intake manifolds, throttle bodies, exhaust manifolds, ect...

If anyone else has any ideas please feel free to add.

[ClubSport]

The cams will not be compatible, because the M42 and S14 use direct acting cams - there are no rocker arms like the M44. The rocker arms have a ratio that increases the valve lift, so the lobes don't need to be as tall. Ever seen a cam-on-bucket cam next to a rocker cam? The lobes are MUCH taller and pointier on the first. There are also differences in lobe profile because the M44 uses roller rockers. You can use much more agressive opening and closing profiles with a roller tip like an M44 than with a flat follower like an M42. In short, they will not work.

Also, I don't think your dealer will allow you to return special orders like cams.

[TiPerformance]

Thanks, I finally figured that out from the diagrams I got from the dealer today, but it still ,makes me mad I can't get any answer on stock cam specs.

I guess I am going to try to get into contact with Bekkers and see if their 4 cylinder cams will work. $470 plus shipping for the performance cam shaft.

[ClubSport]

Stock cams for the M42 are 242 degree duration and 9.7 mm (.381") lift, if that helps. Dunno about the M44. Probably similar. I'd also like to know what engine bekkers 4-cyl cams are for.

[TiPerformance]

Bekkers do not have a application for the m44 engine which is a big disappointment. I was told that Bekkers cams are for the M10 engine. I also tried www.kentcams.com which they list a cam for the M44 I was told from one of their distributors that I would either need to get new stock cams or send in mine so they could regrind them at a cost of $450 + shipping fees. I was told they they would not add material, that they would just regrind a new profile. So does that more than likely means that valve lift will not increase. I have Kent cams specs so essentially I could take my cams to any machine shop and have them do the same thing as kent.


Are there any other companies that make cams for the M44 engine?

[318tibimmer]

Like you said in your first post, BMP Designs has them. But I know that they are kinda expenceve. You might check and see if you can get a custom grind from a place like Comp Cams. I have not checked but I am sure they could do it for you just give them the specs that you want and then they will make it custom for your application.

[TiPerformance]

I talked to a guy today at work who builds race engine and his son is into hondas, he told me that even from a stock regrind I can gain valve lift and if I have the right specs I can obtain a decent increase in power. So I am going to try to find a place locally to grind cams for me and if they are reputable I will see if I can't have them tweek Kent's specs a little.

[bimmerboi318]

with a stock cam that has been reground, it may be possible to gain lift with a higher ratio rocker arm. im not sure how my valvetrain works, but if you said the m44 has rocker arms, its possible. bmp design would be my best bet though. although a set of cams with the right valve springs, retainers, etc.. is going to set you back over 1200 bucks i believe.

anyways, how much of an increase in power would we see with our 1.8's and 1.9's with some hot cams? im wondering if it would hurt our low end too much...

[ClubSport]

You can increase valve lift with a regrind. The cam just has a smaller base circle and you need longer valve stems to make up for that.

[Freedy]

anyone have some pictures of what a valve stem looks like? or is the stem just the long part of the valve? Do you need new valves to increase stem length would be the best question.

[ClubSport]

Yes, you need new valves to increase the length of the stem. It's all one piece.

[TiPerformance]

If you get a higher lift cam you will not have to get new valves to increase the legnth of the stem, because the valves aren't really opening that much more, if anything new vavle springs. The only way I could see the need for new valves is if you were to go with a very high lift cam and then the pistons would have to be cut with valve reliefs so that there wouldn't be contact between the pistons and the valves.

[Freedy]

thats what I was thinking, and at that point you could recontour the pistons to get an even closer tolerance with the flat part of the head. That thing where the air gets crushed into the center of the chamber when at peak compression to get a nice swirl. Whats that called? Pent roof combustion chamber effect or something?

[ClubSport]

Nope. Depends what kind of cam you're getting. If you're getting your stock ones reground to a higher lift, you need longer valves. How do you think you can grind more lift into a cam lobe? You you do it by making a smaller base circle, meaning you don't make the point of the lobe taller, you make the back shorter. In that case the valve stem won't be in contact with the lifter anymore.

If you're getting an aftermarket high lift cam, this will be ground with the same size base circle as your stock cam, meaning you won't need longer stems. This is the better way to go.

In either case, you'll want to upgrade the valve springs when going with a very big lift to avoid float. Too big a lift, and yes, you will have to cut reliefs in the pistons.

Freedy, I believe you are referring to squish in the last sentence of your post.

Originally Posted by TiPerformance

If you get a higher lift cam you will not have to get new valves to increase the legnth of the stem, because the valves aren't really opening that much more, if anything new vavle springs. The only way I could see the need for new valves is if you were to go with a very high lift cam and then the pistons would have to be cut with valve reliefs so that there wouldn't be contact between the pistons and the valves.

[bimmerboi318]

Would it be possible to get taller bucket lifters instead of new valves? I understand the part about a longer valve stem, it makes sense. But having a smaller base circle would be like having ALOT of lash. You fix a little bit of lash with shims. Couldnt you go a step farther and get taller lifters? Either way, something has to be done to keep the valve in a mechanical link to the cam. And valve springs alone arent going to help that I'm pretty sure.